Tullow Oil has started oil production from the Tweneboa, Enyenra, Ntomme (TEN) fields, located offshore Ghana.
The oil will flow to the floating production, storage and offloading (FPSO) vessel Prof John Evans Atta Mills.
In May 2013, the Government of Ghana approved the plan of development for the offshore field.
Tullow said that the TEN start-up process is well advanced and further expects oil production to increase gradually towards the FPSO capacity of 80,000bpd through the rest of this year.
The average annualised production from TEN is expected to be around 23,000bpd gross during this year.
Tullow operates the TEN fields with a 47.175% stake.
Joint venture (JV) partners are Anadarko Petroleum (17%), Kosmos Energy (17%), Ghana National Petroleum (15%) and PetroSA (3.875%).
Tullow Oil CEO Aidan Heavey said: “This is an important moment for Tullow as production begins from our second operated development in Ghana.
“I thank the Government of Ghana, the Petroleum Commission and our partners, GNPC, Anadarko, Kosmos and PetroSA, for their support and co-operation since we made the first discovery in 2009."
The FPSO arrived in Ghanaian waters on 2 March, was constructed in Singapore.
Built by MODEC, the vessel will be operated by MODEC Ghana on behalf of the TEN JV partners.